Luminair



Feb. 2, 1932. s. ENGLISH I LUMINAIR Filed Jan. 24, 1929 INVENTOR ATTORNEY V Patented Feb. 2, 1932 warren stares mam orrica SOLOMON ENGLISH, or LoNnoN, ENGLAND, ssIoNoRiro I-IOLOPHANE COMPANY, INo.,

on NEW YORK, N. Y., A conrorm'rroN on NEW YORK LUMINAIR I Application filed January 24, 1929, Serial No. 334,613, and in Germany February 3,1928.

This invention relates to a luminair which has a particular utility for the illumination of streets and roads, but it can be applied to other lighting systems. The device comprises the use of several independent light directing or refracting sections, fitted inside of a lantern or other casing surrounding the light source. Between the sections there can either be sections of other light directing devices, plain sections or open sections. By the use of these sections different lighting results can be obtained, as the mechanism can be adapted so that the sections are interchangeable. The invention is more particularly described hereafter.

The invention is hereby described in terms of a luminair for streets, and while any light source can be used, a device for use with'an incandescent gas flame has been designed to outline the features of the invention, as modern improvements in connection with luminairs for gas lit thoroughfares are almost unknown, although there are many streets still lit with gas.

In the device hereinafter described, several independent light concentrating or refracting sections are fitted separately from each other, inside the lantern or other casing surrounding the source of light as shown, these sections being so placed that a space is left between them. The independent sections can be shifted to obtain a distribution desired in any part-icularlocality.

The invention is illustrated in the accompanying drawings applied to street lighting devices in which Fig. 1 shows a side view of a gas lantern, the light concentrating sections being fitted on two sides of the source of light, which consists of three incandescent gas burners.

Fig. 2 shows a sectional plan view of the device, under line AB of Fig. 1;

Fig. 3 shows a curved distribution of light in a horizontal plane through the source of light, and

Fig. 4 shows a curve of distribution of light in a vertical plane, passing through the source of light.

In the accompanying drawings, 1 is the casing of a gas lantern; 2 indicates the cover of. the casing and 3 indicates the source of light and 4E indicates thelight concentrating sections. In the diagram of Fig. 3 showing the distribution of light thedotted line 5 refers to the'distr-ibutionof the light from the naked source of light, i. e., with all enclo sure'sabsent, and the line .6. shows the distribution of light passing through the light concentrating sections. a-p'plyto the diagram shown in Fig. 1in a vertical. plane. In these figures the light concentrating sections areshown at 4'.

.,Tlie term light; collecting sections is intended-toinclude plane, curved or open sections :of transparent pressed glass, provided on one or both surfaces with light refracting or distributing prisms. These light concentrating sections are designed either as plane: glass slabs or panes or as curved constituent parts ofa' ring out from the mantle The same remarks ofa cone or cylinder. When made in a single piece, as illustrated in the drawings, thelight concentratingsections.are designed in such manner that the outer side,i. e. the-side which is situated'furthest from the source of light is provided with light directing distributing prisms running in a horizontal direction, whilethe'central portion of the inner sideis-a smooth surface without prisms. On both sidesofthis smooth surface light refractin'gp risms are arranged running ver-' .ticaland symmetrical to the extreme end of the light concentrating sections. The angles of these prisms are suitably designed in such a manner that they become progressivelymore acute :from the center portion, so that the rays of light which strike these jprisms are deflected as much as possible in the direc tion, or parallel to the central line of the roadway," d

The light concentrating sections 4 are intended to be fitted around the source of light, so that they are substantially perpendicular to the road surface. It follows therefrom,

that for street lanterns employed in the illumination of a straight street without intersections that two light concentrating sections 180 apart would be employed. If the axis of the street is not straight, the light concentrating sections will not be situated 180 apart, but the center of the section will substantially coincide with the center line of the street. In the case of a lantern placed at the point of the intersection of two streets, 5 or at a point where a side street branches off from a main street, more than two light concentrating sections will have to be employed and these sections will be fitted in relation to the source of light. The purpose of the use of these light concentrating sections is to insure that large portions of'the light radiated from the source of light will be diverted in definite directions determined in advance, i. e., in the direction of the axis of the street, while other portions of the light radiated are allowed to pass freely. When so desired, additional light reflecting or refracting sections may be interposed to fill these open segments to produce desirable distributions or to augment the concentration up and down the street and suppress the light at right angles to the street. The result is that the major part of the rays of light are deflected downward in a predetermined manner by the horizontal prisms fitted on the outer surface of the light concentrating sec tions, and can be employed usefully for illuminating the surface of the street. The vertical prisms, formed on the inner surface diffuse the light without changing its vertical direction.

In the form shown in the drawings, an open space has been left between the sections for the purpose of preventing cracking or bursting of the device due to the great heat generated by the source of light. The advantages of light distributing sections which can befitted in any desired manner around the source to obtain desired distributions whether for gas or for any other source-of light is apparent.

I claim:

The combination with a lamp having a; glass enclosure containing a light source,

of a plurality of light directin elements horizontally disposed in said enc osure and arranged at opposite sides of the light source, each of said elements having its outer side provided with horizontal prisms extending from end to end of the element, and the inner side of each element, with the exception of the medial portion thereof, having vertically disposed prisms, the inner surface of said medial portion being plain.

Signed at 8 St. Martins Place, London, England this 10th day of January, 1929.

SOLOMON ENGLISH. 

